Lawmakers are competing to influence the next big review of California high-speed rail, underscoring the project's new political vulnerability.

Following a devastating state study issued Tuesday, a congressional watchdog agency is considering making its own assessment of the ambitious, $98.5 billion rail plan. Capitol Hill advocates already are trying to shape the questions that investigators ask, possibly hoping for answers helpful to their respective causes.

"Trying to get an objective response that is based in the facts rather than in politics, is essential," Rep. Jim Costa, D-Hanford (Kings County), said Wednesday.

Charles Young, a spokesman for that office, said Wednesday that the agency's formal decision on whether to do a study could take several more weeks.

A new federal study would add to other studies, including the sharply critical review issued Tuesday by the California High-Speed Rail Peer Review Group. The California panel called the current rail plan "not feasible" and urged state legislators not to issue $2.7 billion in bonds.

In their Dec. 20 request to the General Accounting Office, high-speed rail skeptics tilted investigators toward questions critical of California's plans. These include citing the state's "questionable ridership and cost projections," as well as the need for future subsidies and the "adverse economic impacts" resulting from seizing private land.

Twelve House members championed the original request for a federal investigation, all Republicans. Ten are from California.

This week, Costa and 10 other House Democrats - eight from California - countered with their own study recommendations. The Democrats, in essence, urged investigators to consider questions that might make California's project look better.